Tylenol Autism and ADHD Lawsuits Advance as Appeals Court Rejects Rehearing

ADHD and autism cases involving prenatal use of acetaminophen will be sent back to a federal judge who will revive the claims and continue going through pretrial proceedings.

A federal appeals court has upheld its decision to reinstate thousands of lawsuits alleging that Tylenol use during pregnancy increases the risk of autism and attention deficit hyperactivity disorder (ADHD) in children.

Johnson & Johnson and its over-the-counter drug manufacturer spin-off, Kenvue, faced hundreds of Tylenol autism and ADHD lawsuits, which allege that the manufacturer failed to warn women that taking the acetaminophen-based painkiller during pregnancy could cause developmental and neurological problems in their offspring.

Originally consolidated in the Southern District of New York in October 2022, U.S. District Judge Denise Cote was assigned to oversee the litigation through pretrial proceedings. However, Judge Cote dismissed the litigation in 2024 after excluding the expert witness testimony plaintiffs needed to show a causal link between Tylenol and developmental problems. With no way to show causation, the claims could not move forward.

Tylenol Autism and ADHD Problems

Acetaminophen, sold under the Tylenol brand name and as an ingredient in numerous other cold and flu medications, is one of the most widely used pain relievers and fever reducers in the world. For decades, it has also been considered one of the safest options for treating pain and fever during pregnancy, when many alternative medications are not recommended.

However, research published in recent years has raised concerns about whether prenatal acetaminophen use may increase the risk of autism and ADHD in children, particularly when the medication is used frequently or for extended periods during pregnancy.

Conflicting research has become a central issue in thousands of Tylenol autism and ADHD lawsuits, which allege that manufacturers knew or should have known about the potential developmental risks but failed to provide adequate warnings to pregnant women. The manufacturers dispute those claims, maintaining that the available scientific evidence does not establish that acetaminophen causes autism or ADHD.

In September 2025, the U.S. Food and Drug Administration (FDA) announced plans to update acetaminophen warning labels to address evidence suggesting a possible association with autism and ADHD. The agency also notified healthcare providers about the potential risks, while acknowledging that a causal relationship had not been established.

The FDA’s action brought renewed attention to the controversy, but questions about the strength of the scientific evidence remain central to the litigation, particularly whether expert testimony linking prenatal acetaminophen exposure to autism and ADHD should be presented to juries.

Tylenol Autism, ADHD Lawsuits

Following Judge Cote’s dismissal of the litigation, plaintiffs filed an appeal of that ruling. In July 2026, the U.S. Court of Appeals for the Second Circuit overturned her decision and reinstated hundreds of Tylenol lawsuits, returning them to the judge for further pretrial proceedings and reigniting the litigation.

On September 10, defendants filed a petition for rehearing, saying more deference should have been given to Judge Cote’s decision. The manufacturers also argued that the reversal does not make the plaintiffs’ expert witnesses admissible and still leaves them without the ability to argue causation.

The 2^nd Circuit rejected the manufacturers’ petition in a brief order issued on October 16, which has not yet been publicly released. However, it appears the panel gave no reasoning for its decision.

As a result, the litigation will continue to move forward, with the cases returning to Judge Cote, who could order plaintiffs and defendants to select several representative claims to serve as potential Tylenol ADHD and autism lawsuit bellwether trials. These would put several lawsuits before juries, allowing stakeholders to see how they are likely to respond to evidence and testimony that would be repeated throughout the litigation.

These cases will be closely watched. While they are not binding on other claims, they could help both sides reach a Tylenol lawsuit settlement agreement, resolving all or most of the litigation.

Families who believe their child’s ADHD or autism diagnosis may have been caused by the use of acetaminophen during pregnancy are being encouraged to submit information for review by a lawyer to determine if they qualify for a claim.

All cases are handled on a contingency fee basis, meaning there are no fees or expenses unless a recovery is obtained in the case.

Sign up for more legal news that could affect you or your family.